From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 14929C7619A for ; Wed, 12 Apr 2023 21:06:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229481AbjDLVG4 (ORCPT ); Wed, 12 Apr 2023 17:06:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39846 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229711AbjDLVGz (ORCPT ); Wed, 12 Apr 2023 17:06:55 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 099337A84 for ; Wed, 12 Apr 2023 14:06:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681333574; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=yrnKHlrl6y09FHQyO1AnY118pk9R47m1lXpkXewp9c4=; b=gaWSUarnFAThEspw5sVGD9uzx+lI7z4ZxQb8T20TGHGMir9N/7+uXgR1mOIinq1cqTXmM6 hyT6K5jxZNkqecTMzUJcbzW4nD3nGL9NSdF1ijcqspxbd9EwPTisCd47CTzxaLqx1z+Yg3 xv36vHeetcEwdvk8Gmxp2pNjQDrj2e8= Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-644-qBSm0qhxPN6y6HrIWsbU7g-1; Wed, 12 Apr 2023 17:06:12 -0400 X-MC-Unique: qBSm0qhxPN6y6HrIWsbU7g-1 Received: by mail-ed1-f71.google.com with SMTP id x1-20020a50ba81000000b0050234a3ad75so5891113ede.23 for ; Wed, 12 Apr 2023 14:06:12 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681333572; x=1683925572; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=yrnKHlrl6y09FHQyO1AnY118pk9R47m1lXpkXewp9c4=; b=K9+i7r4w2SrEPYl3gl70op3KWXPkYHx7NJJ9ICm4gmltxf6sfow4Nb7PJDi/xdBiiO M7l+1kn8vkaNxjggx/XMeXIG8gBa/dzolfkYPojCwlUSL5+2ru2Rd9lP3Fp0L29zmtJc 8FJee8rbz9V5YNtKDC37wDIpHhto9UfosAi1OYoe6Oqs6NojvbiQqCYUTFAGCW806Cqw LS3MvEVdpTgv02tujhZKKQveZfdd+f5nuqU9Kp2Nw+8LG8SSsg5orFE7ATTPv5Drbhz9 l8418y3tFjZZC69W5L0VfvibZEckwEOmXV4nJtOd5kaP3GKbT+EjaFzaBT9z6kVn4inn 6REg== X-Gm-Message-State: AAQBX9eBLFdnBzdLr9P8yYpxrHvgwbX6C5r6C7kr31l3sU5TXI1UcW6P QsbaBorD0yk4f+r0Gyugpt6Wd9ZFsRd28yrGQ3Vj9ii/h0S8gJku7zNTJuow4Nj4Vx5yE4p2JIS eCKcuzHcFyhRTSavLubN6tA== X-Received: by 2002:a17:906:1c91:b0:94b:28dc:e748 with SMTP id g17-20020a1709061c9100b0094b28dce748mr215902ejh.64.1681333571718; Wed, 12 Apr 2023 14:06:11 -0700 (PDT) X-Google-Smtp-Source: AKy350ZnOY2/8OmziTqtJx1zTm6KraNb3L4vDlmeHRkXCOwgXGtcmNzqVF/8RbNkcqBZPrxYJ2sdDw== X-Received: by 2002:a17:906:1c91:b0:94b:28dc:e748 with SMTP id g17-20020a1709061c9100b0094b28dce748mr215890ejh.64.1681333571407; Wed, 12 Apr 2023 14:06:11 -0700 (PDT) Received: from ?IPV6:2001:1c00:c32:7800:5bfa:a036:83f0:f9ec? (2001-1c00-0c32-7800-5bfa-a036-83f0-f9ec.cable.dynamic.v6.ziggo.nl. [2001:1c00:c32:7800:5bfa:a036:83f0:f9ec]) by smtp.gmail.com with ESMTPSA id wz10-20020a170906fe4a00b0094a6e7075eesm4098706ejb.41.2023.04.12.14.06.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 12 Apr 2023 14:06:10 -0700 (PDT) Message-ID: <3bd58e16-53c7-0a81-45be-26fe1443b65a@redhat.com> Date: Wed, 12 Apr 2023 23:06:10 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.7.1 Subject: Re: "leds: trigger: use RCU to protect the led_cdevs list" triggers RCU error checks To: Johannes Berg , Pavel Machek , Lee Jones Cc: Linux LED Subsystem References: <600cc06e-081d-cd90-947d-f8988f1af194@redhat.com> <73428542-6aaf-5db3-9d67-f73cf1082695@redhat.com> <0e0bf2a681db18c20eb9913b23d8ff2d5fddfe90.camel@sipsolutions.net> Content-Language: en-US, nl From: Hans de Goede In-Reply-To: <0e0bf2a681db18c20eb9913b23d8ff2d5fddfe90.camel@sipsolutions.net> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-leds@vger.kernel.org Hi Johannes, On 4/12/23 10:13, Johannes Berg wrote: > Hi, > >> So I just checked and the following LED drivers all have >> a blink_set() implementation which calls mutex_lock() >> and/or does I2C transfers: > > > > Yay ... > So not sure. Clearly it's a long-standing issue, and given that many > drivers are affected probably better to fix it in the LED core, but I > don't really know my way around it very well either. I think I've come up with a solution for this. I'll Cc you on the patch-set for this when it is ready. Regards, Hans